Fountain beverages have been installed in bars, restaurants, drug stores and other locations on a worldwide basis which are provided with apparatus for carbonating water received from a source of potable water, and mixing it with a flavored syrup to make a variety of soft drinks as well as alcoholic beverages. However, the chemistry of water differs considerably from place to place; important differences exist in the amounts of dissolved oxygen, pH values, as well as in a variety of other substances dissolved in and carried by the water. Although water may be treated at point of use for the purpose of removing or neutralizing contaminants in the local water supply, the various known and more frequently used modes of water treatment do little to improve the water for subsequent carbonation. This is true, in part, because dissolved oxygen is not generally considered undesirable in a water supply. Fresh clear water is normally full of oxygen and a balance is maintained by the biochemical functions of aquatic plants and animal life. Moreover, it is common for municipal water, after filtration, to be passed through an aerator (either in the form of fountains or water jets) to saturate it with oxygen before it is treated with chlorine. However, a substantial percentage of fountain services in the United States produce less than entirely satisfactory carbonated drinks due primarily to high amounts of dissolved oxygen in the water. Thus, for carbonation of water, dissolved oxygen is undesirable.
Moreover, the problem appears to be aggravated by other substances dissolved or carried in the water. It may have suspended material, such as clay particles, a large number of different dissolved solids, bacteriological and biological contaminants, chemicals such as phenols which, in a few parts per million, may be associated with traces of chlorine. Iron, manganese, lead and nitrogen are frequently found in small quantities in water supplies. The presence of calcium carbonate indicates water hardness, which is due primarily to the presence of dissolved calcium and manganese salts. The result is that carbonated drinks may be less tasty because of the reduced carbonation, and therefore less desirable to consumers. It is not uncommon, of course, to provide an apparatus for softening water at point of use. One method of softening water is to pass it through a granular zeolite which may be a natural occurring or artificially hydrated aluminum silicate, wherein the water softening action occurs due to the zeolite replacing calcium ions from the water with the zeolite's sodium ions. However, for the purposes of carbonation, sodium is considered undesirable and should therefore be removed from, not added to, the water prior to carbonation.